What Lies Below (2020) is a gripping sci-fi horror thriller that masterfully blends family drama with unsettling supernatural dread. The film follows 16-year-old Libby, who returns from camp to find her mother, Michelle, deeply involved with a new boyfriend, John Smith. Portrayed with eerie charm by Trey Tucker, John's flawless appearance and intellect immediately strike Libby as inhuman, sparking a tense battle of intuition against her mother's infatuation.

Directed by Braden R. Duemmler, the movie builds a claustrophobic atmosphere, using its isolated lakeside setting to amplify the sense of entrapment and mystery. Mena Suvari delivers a compelling performance as Michelle, caught between maternal love and romantic obsession, while Ema Horvath shines as the perceptive and increasingly desperate Libby. The plot unfolds with slow-burn tension, weaving elements of biological horror and psychological thriller as Libby's investigations reveal horrifying truths about John's origins.

Despite its modest IMDb rating, What Lies Below offers a unique take on the 'stranger in the house' trope, elevated by strong performances and a chilling, ambiguous premise. It's a must-watch for fans of indie horror seeking a thought-provoking, character-driven story that questions what it means to be human. The film's 87-minute runtime ensures a tight, suspenseful experience perfect for a thrilling movie night.